With increasing recognition of the health and psychosocial challenges in developing countries, more research in these countries is essential. Research collaborations between wealthier and less wealthy countries are, however, complex. A partnership model has been proposed which emphasizes the importance of mutually respectful and beneficial relationships in international research. Using an example of a mother-infant intervention project in South Africa we describe the elements of an equitable partnership model of research. An issue which has been overlooked, however, is the reality of power differentials within the poorer countries themselves. We show that there are many intersecting levels of relationships within intercountry research, and suggest that power dynamics within countries deserves equal attention as international issues. Based on our experiences, we present some tentative guidelines for international research which builds long-term capacity and recognizes the importance of multiple levels of analysis and interaction.